Late Filing Your Self Assessment: Penalties and What to Do
If you have missed the 31 January filing deadline, act quickly. The penalties escalate over time, so the sooner you file, the less it costs.
Penalty Timeline
| Time late | Penalty | |-----------|---------| | 1 day | £100 (immediate, even if no tax owed) | | 3 months | £10/day for up to 90 days (max £900) | | 6 months | Greater of £300 or 5% of tax owed | | 12 months | Greater of £300 or 5% of tax owed |
Plus late payment penalties and interest on any unpaid tax.
What to Do Right Now
- File your return immediately. Every day you delay increases the potential penalties.
- Pay any tax owed. Minimise late payment penalties and interest by paying as much as you can as soon as possible.
- Contact HMRC. If you have a reasonable excuse for filing late (serious illness, bereavement), appeal the penalty.
- Set up a Time to Pay arrangement. If you cannot pay in full, call HMRC to discuss spreading the payment.
Reasonable Excuses
HMRC may cancel penalties if you had a genuine reason for missing the deadline: serious illness, bereavement, fire or flood, or HMRC system issues. Being busy or forgetting is not a reasonable excuse.
Preventing It Next Time
File early. You can submit your return from 6 April after the tax year ends. Accounted keeps your records up to date all year so you can file as soon as the tax year ends.
MTD is coming. Accounted is already compliant. Start free and be ready before the deadline.
Tax & Compliance Specialists
Our tax specialists have decades of combined experience in UK sole trader and small business taxation, MTD compliance, and HMRC submissions. All content is reviewed against current HMRC guidance before publication and updated quarterly to reflect legislative changes.
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